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Journal of Shanghai Jiaotong university(Science) 2009年第4期14卷 398-403页

作者：张振东栾茂田金丹郭莹聂影 State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Institute of Geotechnical engineering School of Civil and Hydraulic EngineeringDalian University of Technology department of civil {2. Huaihai Institute of Technology

By using the soil static and dynamic universal triaxial and torsional shear apparatus, a series of combined cyclic shear tests are performed to simulate the rotation in the principal stress direction induced by ocean wave. The tests include the cyclic preloading tests and liquefaction tests in the second loading on saturated loose sand with a relative density of 30%. The all tests are consolidated under isotropic condition. The effect of the cyclic preloading on the resistance to liquefaction of saturated loose sands under the condition of continuous rotation in the principal stress direction is investigated. Experimental data indicate that the void ratio of saturated sands has a negligible reduction after cyclic preloading. With the increase of the intensity of cyclic preloading (in the amplitude and in the number of cycles), the resistance to liquefaction in the second loading is increased continuously under the condition that the liquefaction does not occur during the cyclic preloading. The reason is that the construction of more stable structure due to the uniformity of the void and the better interlocking of the particles when the cyclic preloading is applied to the saturated sand.

关键词： saturated sand liquefaction continuous rotation in the principal stress direction cyclic preloading second loading void ratio

FUZZY OPTIMAL DECISIONS FOR MULTIOBJECTIVE FLOOD CONTROL SYSTEM OF CASCADE RESERVOIRS

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Journal of Hydrodynamics 1999年第3期11卷 6-13页

作者： Cheng Chun tian civil engineering {2., dalian university of technology,dalian 11602., P.R.China (Received June 13,1998)

Based on the practice of reservoir operation, a decision making model of multi objective flood control of cascade reservoir system is presented, which is realistic and effective, combining traditional optimal techniques with fuzzy set theory. In the present paper, the operation alternative is chosen as the decision variable, the outflow process as the state variable, and optimal operation decisions are determined by the fuzzy optimal technique. Finally, the model is delineated by taking a case study of comprehensive flood operation for a cascade reservoir system.

关键词： multiobjective flood control multireservoir flood control fuzzy optimal decision recursion matrix

Wave-current forces on bipiles in parallel array

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Acta Oceanologica Sinica 1992年第3期11卷 453-462页

作者： Li Yucheng, Wang Fenglong and Wang Hongrong department of civil {2., dalian university of technology, dalian 11602., China

-The inline and lift forces on bipiles in parallel array induced by both irregular waves and currents were investigated experimentally in this paper. The characteristics in both time and frequency domains of inline, lift and resultant forces as well were analyzed. The grouping effect coefficients of inline and resultant forces on two piles related to KC number and relative spacing parameters are given. A comparison of the magnitude and direction of resultant forces on two piles in parallel array with the corresponding values for single cylinder is also made.

关键词： Wave-current forces on bipiles in parallel array

Multi-symplectic method to analyze the mixed state of Ⅱ-superconductors

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Science China(Physics,Mechanics & Astronomy) 2008年第12期51卷 1835-1844页

作者： HU WeiPeng1↑ & DENG ZiChen1,2.1 School of Mechanics, civil engineering and Architecture, Northwestern Polytechnical {2., Xi’an 710072. China 2.State Key Laboratory of Structural Analysis of Industrial Equipment, dalian university of technology, dalian 11602., China School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi’an China State Key Laboratory of Structural Analysis of Industrial Equipment Dalian University of Technology Dalian China

The mixed state of two-band II-superconductor is analyzed by the multi-symplectic method. As to the Ginzburg-Landau equation depending on time that describes the mixed state of two-band II-superconductor, the multi-symplectic formulations with several conservation laws: a multi-symplectic conservation law, an energy con- servation law, as well as a momentum conservation law, are presented firstly; then an eighteen points scheme is constructed to simulate the multi-symplectic partial differential equations (PDEs) that are derived from the Ginzburg-Landau equation; finally, based on the simulation results, the volt-ampere characteristic curves are obtained, as well as the relationships between the temperature and resistivity of a suppositional two-band II-superconductor model under different magnetic intensi- ties. From the results of the numerical experiments, it is concluded that the notable property of the mixed state of the two-band II-superconductor is that: The trans- formation temperature decreases and the resistivity ρ increases rapidly with the increase of the magnetic intensity B. In addition, the simulation results show that the multi-symplectic method has two remarkable advantages: high accuracy and excellent long-time numerical behavior.

关键词： two-band Ginzburg-Landau equation mixed state multi-symplectic conservation law

COMPUTATION OF FREE SURFACE FLOWS WITH HIGH RESOLUTION FINITE ELEMENT SCHEME

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Journal of Hydrodynamics 2003年第3期15卷 22-27页

作者： Jin Sheng, Zhang Ri-xiang, Pu Gao-jun department of civil {2., State Key Laboratory of Offshore {2., dalian university of technology, dalian 11602., China, departmentofcivil{2. StateKeyLaboratoryofOffshoreEngineeringDalianUniversityofTechnologyDalian116024China

A high-resolution finite element scheme is developed for the computation offree surface problems. The present higher-order accuracy scheme is obtained through the introductionof the difference of almost equal amount of diffusion and antidiffusion, where the antidiffusion isformulated as approximation to diffusion making use of consecutive gradient. The non-oscillatoryproperties are secured by limiters to preserve positivity constraints. The implement of the schemeis based on semi-discrete form and can be considered as reconstruction of the coefficient matrix ofalgebraic system, so, it can he conveniently used by either structured or unstructured meshes. Thepower and flexibility of the present high resolution VOF-FEM approach is validated by examplesincluding convective transport, dam breaking flow, and stilling basin flow in hydraulic engineering.

关键词： free surface flow high resolution finite element scheme

An effective and practical method for solving an unnegligible problem inherent in the current calculation model for multi-support seismic analysis of structures

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Science China(Technological Sciences) 2010年第7期53卷 1774-1784页

作者： LIU GuoHuan2. GUO Wei1 & LI HongNan2.1 National engineering Laboratory for High Speed Railway Construction, School of civil engineering and Architecture, Central South university, Changsha 410075, China 2.Faculty of Infrastructure engineering, dalian university of technology, dalian 11602., China 2. Faculty of Infrastructure engineering Dalian University of Technology Dalian 116024 China1. National Engineering Laboratory for High Speed Railway Construction School of Civil Engineering and Architecture Central South University Changsha 410075 China

In the seismic analysis of extended structures subject to spatially varying motions, the displacement input model instead of acceleration model is usually adopted for accurate results. In this paper, a more detailed and comprehensive analysis of the displacement input model is carried out and the research shows that there exists an unnegligible problem in the current displacement model, which leads to the irrationality and unconvergence of some calculated results such as base shear etc. Based on the situation, an effective method named massless rigid element (MRE) method is presented to solve the problem. Moreover, the rationality and accuracy of the method are further assessed and the method is applied to a transmission tower-line system project using the commercially available structural analysis software SAP2.00. The theoretical and numerical analyses indicate that the MRE approach is not only feasible with sufficient computational accuracy but also practical and can be easily implemented using the commercially available finite element software such as SAP2.00.

关键词： extended structures seismic responses spatially varying motions displacement input model massless rigid element (MRE) transmission tower-line system

Changing Rule of Carbon-Enriched Zone and Diffusion Behavior of Carbon in Aging 0Cr6Mn13Ni10MoTi/1Cr5Mo Dissimilar Welded Joints

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Journal of Materials Science & technology 2004年第3期20卷 307-310页

作者： Zheng LIU Ligang WANG Lai WANG department of Materials engineering,{2., dalian 11602.,China Dept. of Mat. Eng. Dalian Univ. of Technol. Dalian 116024 China

The microstructures, the changing rule of carbon-enriched zone, the diffusion behaviors of elements C and Cr, and thecarbide type of 0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints after aging at 500℃ for various times and afterlong-term service in technical practice were investigated by using the optical microscopy electron probe microanalysis,scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The results show that in aging0Cr6Mn13Ni10MoTi/1Cr5Mo dissimilar welded joints, the main carbides are M_3C and a few carbides are M_7C_3 andM_(2.)C_6. The M_3C carbide decomposition and dissolution with increasing aging time or aging temperature and theanti-diffusion of C and Cr cause the decrease and disappearance of the carbon-enriched zone. The results are differentfrom those of the A302.1Cr5Mo dissimilar welded joints in previous studies.

关键词： Dissimilar welded joint Aging Diffusion Carbides

SITMILARITY LAW FOR HYDRAULIC DISTORTED MODEL

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Journal of Hydrodynamics 2003年第1期15卷 67-71页

作者： Wang Yong taodepartment of Environmental Science and engineering, {2. of Science and technology of Suzhou, Suzhou 2.5011, ChinaCui Li department of civil engineering, dalian university of technology, dalian 11602., China Dept. of Environ. Sci. and Eng. Univ. of Sci. and Technol. of Suzhou Suzhou 215011 China Dept. of civil Eng. Dalian Univ. of Technol. Dalian 116024 China

Newton's general similarity criterion was applied to the distorted model. Theresults for the similarities of gravity force, drag force and pressure force are identical withthose derived from relevant differential equations of fluid flow. And the selected limits of thedistorted ratio were studied and the simulation of roughness coefficient of distorted model wasconducted by means of hydraulic test.

关键词： distorted model similarity criterion distorted ratio simulation ofroughness coefficient

Mechanism of local scour around submarine pipelines based on numerical simulation of turbulence model

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Acta Oceanologica Sinica 2006年第2期25卷 142-152页

作者： L Lin1*, LI Yucheng1,3, CHEN Bing2.. State Key Laboratory of Coastal and Offshore engineering, dalian university of technology,{2., China2. School of civil and Hydraulic engineering, dalian university of technology,{2., China3. R&D center of civil engineering technology, dalian university, dalian 11662., ChinaReceived 2. July 2.05 accepted 14 December 2.05 State Key Laboratory of Coastal and Offshore engineering Dalian University of Technology Dalian 116024 China RandD Center of civil engineering {2. Dalian University Dalian 116622 China School of civil and Hydraulic engineering Dalian University of Technology Dalian 116024 China

The mechanism of local scour around submarine pipelines is studied numerically based on a renormalized group (RNG) turbulence model. To validate the numerical model, the equilibrium profiles of local scour for two cases are simulated and compared with the experimental data. It shows that the RNG turbulence model can give an appropriate prediction for the configuration of equilibrium scour hole, and it is applicable to this situation. The local scour mechanism around submarine pipelines including the flow structure, shear stress distribution and pressure field is then analyzed and compared with experiments. For further comparison and validation, especially for the flow structure, a numerical calculation employing the large eddy simulation (LES) is also conducted. The numerical results of RNG demonstrate that the critical factor governing the equilibrium profile is the seabed shear stress distribution in the case of bed load sediment transport, and the two-equation RNG turbulence model coupled with the law of wall is capable of giving a satisfying estimation for the bed shear stress. Moreover, the piping phenomena due to the great difference of pressure between the upstream and downstream parts of pipelines and the vortex structure around submarine pipelines are also simulated successfully, which are believed to be the important factor that lead to the onset of local scour.

关键词： submarine pipeline mechanism of local scour renormalized group turbulence model large eddy simulation piping

Experiment and Numerical Simulation on Axial Compressive Performance of Autoclaved Fly Ash Solid Brick Masonry Columns

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Transactions of Tianjin university 2011年第6期17卷 454-460页

作者：徐春一刘明周海鹰 Faculty of Infrastructure engineering Dalian University of Technology School of civil engineering Shenyang Jianzhu University

To study the influence of slenderness on the axial compressive performance of autoclaved fly ash solid brick masonry columns, compression experiments were conducted on 12.samples of autoclaved fly ash solid brick masonry column and 4 samples of fired clay brick masonry column. The damage patterns and compressive performance were compared and analyzed. The experimental results indicate that the compressive bearing capacity decreases as slenderness increases from 3 to 18, and the compressive bearing capacity of the autoclaved fly ash solid brick masonry columns is lower than that of the fired clay brick masonry columns. The formulae for the axial compressive bearing capacity of autoclaved fly ash solid brick masonry columns were derived based on the experiments. The nonlinear FEA program ANSYS was adopted to simulate the behaviors of masonry columns. By comparing the simulation results and experimental results, it is shown that the simulation results agree well with the experimental ones. The rationality and applicability of the simulation results were verified.

关键词： masonry autoclaved fly ash solid brick compressive bearing capacity slenderness numerical simulation